Improved vulcanizing-flask for dentists



E. T. STARR.

Vulcanizing Flask for Dentists.

Ptented Aug, 14, 1866.

Invn ?071- UNITED STATES PATENT OFFICE.

ELI T. STARR, OF PHILADELPHIA, PENNSYLVANIA.

IMPROVED VULCANIZING-FLASK FOR DE NTISTS.

Specification forming part of Letters Patent No. 57,210, dated August 14, 1866.

To all whom it may concem:

Be it known that I, ELI T. STARR, of the city and county of Philadelphia, in the State of Pennsylvania, have invented certain new and useful Improvements in Vulcanizing- Flashs for Dentsts Use and I do hereby declare that the following is a full, clear, and eXact description of the same, reference being had to 'the accompanying drawings, making a part of this specification, in which- Figure lis a plan or top view. Fig. 2 is an inverted plan View. Fig. 3 is a central vertical transverse section. Fig. etis a partial side View.

Similar letters of reference indicate corresponding parts in all the figures.

The fiashs heretofore employed by dentists for noldin g and V ulcanizing rubber-worh have been open to the objection that when their lowerportions have been made of the proper depth for molding whole dentures, in which the line of division between the two portions of the mold is required at the rim of the plate, they have been too shallow for properly molding those artificial gums that are designed to rest upon the natural gums whenplaced in the mouth, inasmuch as in this case the line of division should be at the crowns of the teeth, which brings the plaster too high above the rini of the flash and affords too little support to the.. teeth when the two parts of the flash are brought together.

This invention is designed to remedy the above-mentioned defect, and also to provide for the more secure retention of the plasterin the flash, and to enable the different parts of the flash to be taken apart more Conveniently than those heretofore devised; andit consists in certain novel means whereby the desired object is obtained. v

To enable others to understand the nature and construction of my invention, I will proceed to describe it with reference to the drawngs. 4

A and B represent two rings of the same slape and circumference, which are fitted together when the flash is used, as more clearly shown in Figs. 3 and 4, there being two spurs, a, upon opposite sides of the circumference of the part B, the said spurs fittinginto holcs or notches form ed in correspondin glugs Z), formed l upon the circumference of the other portion, A. One part of the circumference of these rings may be made nearl straight, as show-n at c c in Figs. l and 2, while the opposite part is rounded or curved, to nearly or quite correspond with the rounded portion of the circumference of a plate of teeth. The outer edges of these rings A B converge inward sonewhat, as shown in Fig. 3, and upon the outer side or edges of the platc A is placed a covering-plate, d, and upon the correspondin g outer side of the ring B is placed another coveringplate, 0. These rings A B and plates d c, when secured together, as will be presently explained, constitute the body of the flash.

The rings Aand Bare of unequal width, the width of the ring A corresponding to the flash for molding whole dentures, in which the line of division between the upper and lower portions of the mold is required to be at the rim of the plate,while the width of theotherrin g, B,corresponds to the depth required in the said lower portion of the flash when used for molding those guns which are intended, when placed in the mouth, to rest upon the natural guns, in which case it is necessary that the lineof division should be at the crowns of the teeth, it being designed to use one ring or the other for the lower portion of the flash, according to the variety of worh to be nolded therein,

The plate d is provided with several holes,f, which are beveled orcountersunh at theirouter ends, so that when the semi-fluid plaster is ponred into the flash a portion flows into the said holes and fills them, together with their countersunh outer ends', so that on cooling the mass of plaster is firnly held tlerein.

The plates d and e, being of the same size and shape, are intercl'angeable, so that the plate d may be used upon either of the rings A B, as may be desired.

Forned' at suitable points n-pon the circumference of the coverin g-plate d are an y required number of laterally-projecting lugs, g, in the outer surface of which are forned oblong recesses l which correspond to the slape and size of the heads' of 'the T-bolts j, and formed in the outer edges of the lugs g are deep notches or Slots n, which extcnd inward to the inner sides of the recesses h. Forncd upon the circumference of the other covering-plate, e, op-

posite the lugs g when the fiask is closed, are correspondinglugs k, in each of which is formed a, Vertical hole, of such size as to allow the screw or threaded end of one ot' the bolts j to pass through it, as more clearly repres'tedin Fig. 4. V

The T-bolts j are placedwith their heads i in the recesses h of the lugsg, and pass through the slots n in the said lugs and through holes in the lugs k, and are provided upon their threaded ends, outside of the said lugsk, With nuts 7', so that by tightening the said nuts 'r the rings A B and plates d e are tightly and securely held together, thus constituting the flasks in a, closed condition, while, by loosening o'r unscrewing the said nuts for a short distande, the said bolts may be pushed upward or iward, soas to bring the heads i out of the reoesses h, and allow' the headed ends of the bolts to be pushed out laterally through and from the slots n, thus enabling the several parts of' the flash to be taken &part without removing the nuts r from the bolts j, and avoiding, in a great degree, the expenditure of time and trouble required in opening the fia sk by separately and entirely removing the clampingbo'lts therefrom, as in the ordinary way.

The mold is formed within the fiask by means of plastehof-paris in the usual manner, and the fiask is also employed in the vulcanizing process in the same manner as the common flash, one or the other of the rings A Bbeing used to form the lower .portion of the flash, and the plate d being used upon one or the other ring, sifiybe desired, all ashereinbefore f ully eX- plained, and the plaster adjacent to the plate d being securely held in place by that portion thereof projecting into and retained by the countersunk holes f in the said plate, and the several parts of the lask being held together by the T bolts, extendin g from the lugs g to the lugs k, as set'forth.

What I claim as new, and desre to secure byLetters Patent, is

1. The combination of the two rings AB and interchangeable plates s 6, substantially as herein' set forth, for the purpose specified.

2. The hol'es f, beve'led or countersunk at their outer ends, in conbnation with the covering-plate A and a ring, A or B, substantially as herein set forth, for the purpose specified.

3. The slotted lugs g, recessed as described,

of the plate s, in coinbination with theT-bolts j, nuts r, and perforated lugs Ic of' the plate 6,'

substantia lly as'herein set forth, for the purpose specified. i ELI T. STARR.

' VVitnesses AY. MUSTIN, Jr., SAMUEL T. J ONES. 

